Split reduction device



Mar. s, 1929. E, s COCK A 1,703,869

SPLIT REDUCTION DEVICE Filed may 5.1927

TIMING RESERVOIR LOCK UP RESERVOIR INVENTOR :ABLE S. cooK ATTOR N EY Patented Mar. 5, 1929 UNITEDI STATES PATENT OFFICE.'

i EARLE S. COOK, OF WILMERDING, PENNSYLVANIA, `ASSIGNOIB. TO WESTINGHOUSE AIR :BRAKEr COMPANY, OF WILMERDING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

SPLIT REDUCTION DEvrcn Application led May 5, 1927. Serial No. 188,940.

pressure in two stages, in which a lirst reduction reservoir is connected to the equalizing reservoir of an equahzing discharge valve mechanism to cause the first reduction inA sure, the equalizing reservoir may vent intoy the two reduction reservoirs instead of only into the lirst reduc-tion reservoir.

One object of my invention is'to provide lmeans for ensuring the prompt separation of the two reduction reservoirs when an application of the brakes is started. Y

lith previous devices, if the leakage from the brake pipe exceeds a predetermined rate,

such that the equaliz'ing discharge valve should fail to open, then the apparatus would fail to function so as to cause a two vstagev p reduction in brake-pipe pressure and the reduction would be effected in av single stage.y

Another object of my invention is to provide a split reduction device in which the two stage reduction in brake pipe pressureA will be secured regardlessof the extent of leakage from the brake pipe. Y

Another object of my invention isto provide means for ensuring that sufficient time will elapse after the first reduction Yin ybrake pipe pressure has been made Vto permitthe slack in the train to gather according to the length of the train, before the secondV reduction in brake pipe pressure will be started.

Y Another object of my invention is to provide means for preventing the time elapsing between Vthe first and the second reductions in Y brake pipe pressure from exceeding `a predetermined amount. f

. n thev accompanying drawing, thev ligle figure is a diagrammatic view, partly in 'section, of a brake equipment embodying my invention. K

The equipment shown inthe drawing is in general qu1te similar to that disclosed inthe prior pending a plication of T. H. Thomas and E. S. Cook, erial No. 109,044, filed May 1.4, 1926.

may comprise a brake valve device 1 vhaving a rotary valve 2, contained in valve chamber 3 and adapted to be operated by a handle 4.v The valve chamber 3 is supplied with luid under pressure from the usual main reservoir 5, through pipe 6 and passage 7. In the casing of the brake `valve device is disposed an equalizmg discharge valve mechanism comprising a piston 8 having chamber 9 at one side connected through passage 10 with the usual equalizing reservoir 11 and having chamber 12 at the opposite side connected through passage 13 with the usual brake pipe 14.

The piston Slis adapted to operate a brake pipe discharge valve 15, for venting fluid under pressure from the brake pipe 14.

Preferably associated with the brake valve device is an application valve device comprislng a piston 16 contained in piston chamber 17 and a slide valve 18, contained in'valve chamber 19 and adapted to be operated by said piston. Piston chamber 17 is connected lto a pipe 20 which leads to a magnet valve' device comprising an electro-magnet 21 and a V.valve 22.

The magnet 21 is controlled according to the trac conditionsand is energized Whenthe traflic conditions are favorable and is deenergized when the tralic conditions are unfavorable. v i

As 'shown in the drawing, the equipmentl Y When energized, the magnet 21 operates to close the valve 22 andvcut off communication when deenergized the valve 22 is opened by the acting of a spring 24 so as to permit fluid under pressure to be vented from pistn rchamber 17 by way of port 23. L

The valve chamber 19 is charged with luid at main reservoir pressure by way 0f passage 7 and passage 25, and from valve chamber 19, fluid equalizes through a restricted ort l26 in piston 16 to piston chamber 17. en the valve 22 is held closed, the pressure in piston chamber 17 equalizes with that in valve chamber 19 and spring 27 then holds the piston 16 Yand valve 18 in'tlie n oriiial release position, as shown in the drawing;

The valve mechanism for controlling the two stage reductionin brake pipe pressure ngay coinprisea controlling valve deviceliaving differential `piston heads 28 and..29, [the piston chan'iher 30 at theouter tace ofthe larger piston 28 being connected toapassagc' 31 and Vpipe 32 which leads to the seat of the application slide valife18. Thepist'on chainloer ratrtlie outer face of the sinaller piston "29 is connected, through 'a passage 34 with the-:brake pipe 14. The pistons 28 and 29 are connecte-inlay a stein 85 adapted' to oper- ',at'e a slide Valve 8,6 contained in-Valve cliaiii- .ber 87', intermediate the pistons 2 8 and 29.

In lthe norinaiv position of the controlling Valve dei7 ce, as shown in the drawing, Valve `chamber 37 is connected through a port 38 Y fic in the slide valve Witlia passage 89, leading to jalo'ck-up reservoir 40; Y

i Vhentlic1` application slidev Valve 18 is in 'release positioii',1ifalife cliainher 87 and' the' lock-up reservoir 40 are connected to the at# inosplieieltliiough'passage 89, passage 94,

past Ycheck Valve 95, passa-ge 96'. passage 97. Vpipe 98, passage 99, cavity 100 in slide' Vallio' 18 andi exhausty port 101. p

rlissociated with the ,controllingV valve' d'evice'isa Valve de ice'fcoinprising a piston 41', 'contain'edfiiif piston clianilier 42 andra slide Valie48, contained in Valve chainlier 44'and adapted tohe operatedhy piston41-l i VIn the iioiinal'position'ot slide valve 36, pistoncliainher 42Y is connected to a restrict- `ed atmospheric exhaust port 45, through passage 46, cavity 47` in slide li/alve and-passage 48V. A spring 45)"actiiig on the sein ot piston 441 tends Vto inaint'ain said pistonano `the Valve 43' in the lett hand position, as

shown in the drawing, 'iii which the iiisti'eduction reservoir 50 is connected'. to the secondi-reduction' reservoir 51 through passage 52,Y cavity iii slide valve 43, passage 54,

7' and pipe A tiiningl reservoir 56`is'con-` nected', through pipe 57 andpas'sage 58 with .Vali/efcliainher 44, which is open to the at-r inosphere by Way of port 59;

For'-coiitroll'ing` the inaXi'niiiin tiine operation'ot piston41underceitainconditioiis to l,behereina'lftei described, aV vali'e 60,` is pio vided for controlling the ,venting of fluid i"ioin pistoncliaiiiher 42'. i i

".Said valve is iiiounted Gliiiflii'ch is subject tothe pressure eta. spring; 62 tending to shift saidpiston so to operate the-Valve fi() to'opeii coniniunicatioii from pist/on chalinher 42 to an atmospheric exhaust porti-63, leading to clianiheiu4.v The chainhei'f 65 at the opposite side, of piston is connected by Ya pipe 66 toV ci-reservoir 67, vwhich reservoiris connected through' a pipe 68, containing a yciioke' plug 69'haviiig'a restricted port? O, with pipe 2O.v

Normally tlie reservoir 67 ischarged with in a pistonV device ythrough tli'e second reduction res Huid under pressure supplied frein piston chainher 17, when the. inagiiet controlled valve' 22 is seated. lilith the reservoir 67 Charged with fluid under pressure, the piston ,61' is niaintii'inodiin vthe position shown in the drawing,-so as to hold the Valve 60 seated.

. For controlling the ininiinuinrtiine operation-orpistoii 41, under certain conditions to `loe hereinafter described, there is provided a 'Valve piston 71,'suliject on one side to the pressure of a spring 72, tcndinrbil to seatthe piston against aV seat ring 7 BQ The area of the valve; piston Within the seat ringisconnected to passage 81 and `pipe 82 and the chainher 74 at the spring side of the valie piston'71 is connectedthroughl'passage 75, and pipe 76 with passage 77 in the 'hi'akeifalve device, throughwhichv` iluid is ventedJ 'lfioiiithe brake pipe 14,"h'y operation of the discharge' Valve 15. .The chamber 74 is also connected when the valve piston -71 is vin its upper position tl'irougli'la-portfSOiiitii a passage 78 Which opens V into the chaiiiber 7 9 at-'the inner seated area ofthe Valve piston. Passage is also directly connected to passage 78 through a restricted port 81.

Vwith, fl'uid'under pressure. WV lien the `l'de valve 18 is nioifedto application position,

the reservoir 82 is connectedv to vpipe j through cavity86in the slide valve,l softhat fluid-under pressuregtroin'ieservoir 82 isfsup-V pliedV to chaiiiher 7 9ct thevalife piston' 71 a'nd to piston'chaniher 8O otpiston i inthe norinal release iosit' ii et the a inlication slide ValVc1'8`, the first i'jei'liictiou` res- ,ervoir 50 is connect-ed` to thc atmosphere vthroug'hfpipe 87, passage 88. cavity`89 in li 'Valve 18, and en liffiustjrport 90.' In ther nning position ot the brake Valve'g'thesecond reduction icseiif'o'ii 51 is lconnected to the atmosphere, through pipe 91, cavitniY 92 in Vtl'ic rotary Valve 2, aiid'eXliaust vport 93. rThe engineer is thus compelled to inove the vbra c valve device so as to cut oli" coinini'inication troni the second reduction,reservoir 51j tothe atmosphere, otherwise the second reductionAV Will he unl'iinited, lsince the' pressure int-lic cqiializinc reservoir Will-con ervoii to the atmosphere at theport 98. p 'Y fV If the tretiicv conditions are uniiaiforahle andthe magnet 21 becomes deenergizcd, due tothe action of the train cont-rol apparatus,

Vthe valve 22 is therelojf` unseated andiiuidy under pressure` is Vented lfrom piston chaniueY to Y vent ,bei1 17, through pipe 20 toV exhaustpoit 28'.l

Piston 16y is then shifted to its'pouterposition and slide `valve 18 isrinoved to application position, in which the equalizing sage 106, cavity reservoir 11 and chamber 9 of the equalizing discharge valve mechanism a-re connected to.

the first reduction reservoir 50, through passage 102, cavity 103 inl slide valve 18, passage 88 and pipe 87. The pressure in the equalizing reservoir is thus reduced by equalization into the iirst reduction'reservoir'50, according to the relative'volumes of the reservoirs,

. and preferably such that the reduction in vpressurewill be about seven pounds.

The piston 8 of the equalizing discharge valve mechanism is then operated to open the valve 15, so that fluid is vented from the brake pipe 14 to the discharge passage 77.

kWhen the brake pipe pressure has been reduced to a degree slightly less than the reduced pressure in the equalizing reservoir 11, the piston 8 is operated to close the valve 15;

The movement of slide valve 18 to appli- -cation position also causes the reservoir 82 to be Connected to'piston chamber 30 throughV passage 84, fcavity 86 in 'slide valve 18,-passage and pipe 32, and passage 31. The piston 28 is then operated by iuid pressure supplied to piston chamber 30 and slide valve 36 is shifted to a position in which piston chamber 42 is'connected-to a source of fluid l pressure,such as a pressure less than main reservoir pressure as supplied from a reducing valve Ydevice .104, through pipe 105, pas- 47 in slide valve 36, and passage 46.

The piston 41 is thus promptly shifted to the right by fluid under pressure, substantially as soon as the application slide valve A 18 is moved to applicationposition. In the right hand position, communication between passages 54 and 52 is cut oli', so that the iirst reduction reservoir 50 is cut off from the second reduction reservoir 51, and venting of iuid from the 'cqualizing reservoir only Vto the iirst'reduction reservoir 50 is permitted.

Fluid at the reduced pressure supplied by the reducing valve device104 also Hows from passage 46 Vthrough a restricted port 107 toV passage 58 and thence throughpipeV 57 to the timing reservoir 56, charging said reservoir at a predetermined rate, according to the size of the restricted port 107. The charging'of said reservoir continues so long as the slide valve 36 is held in-its lowerposition. AThe lock-up reservoir is now charged with fluid from the brake pipe, as supplied through passage 108, cavity 100 in applicationslide valve 18, passage 99-pipe 98, Vpassage 97, rarity, 109 in slide valve 36,.'and passage 39, The movement offslide valve 36` also connects valve chamber 37 to the atmosphere, through port 38 and exhaust port 110, soV that any fluid leaking into the valve Vchamber will be y vented, and` building up of pressurein said chamber will be prevented. y

Vhen fiuid under pressure is supplied from reservoir 82 to piston chamber 30, it is also pipe 76 through therestricted exhaust port 111. l

The size of the restricted port 81 is such as toy reduce'the pressure in the piston chamber 30 suliciently to permit the brake pipe pressure in piston chamber 33 to effect the upward movement of the piston in a lpredetermined time, for example, ten seconds. During this time, the timing reservoir 56 is being charged with fluid under pressure, as hereinbefore described. I

When the pistons 29 and 28 moveupwardly .after the predetermined time interval', the

timing Areservoir 56 starts to blow down through cavity 47 in slide valve 36, passage 48, and restricted exhaust port 45, and after a predetermined period, for example, ten

seconds, 'the Vpressure in the timingV reservoir v56will have been reduced suiciently to rmit the piston 41 to be'shifted to the left'by the spring 49. The slide'valve 43 is then shifted to the positionY shown in the drawing, in which thefirst reductionreservoir 50 is connected to the second reduction reservoir e 51 through cavity k53 in the slide valve. p The second reduction -in brake pipe pressure is-then started by the equalization of the lequalizing reservoir 11 into the second reduction reservoir 51 and the corresponding action of the equalizing discharge valve 15;

The fluid in reservoir 82 continues to blow Y* down until the pressure of the spring 72 exceeds'the Huid pressure acting on the upper facev of the valve piston V71 and then said valve pistonpisshifted to its upper position, and uidremaining inthe reservoir 82 is more rapidlyvented to passage 75, by way of the larger port. 80, which is uncovered by the upward movement of the valve piston.

The How area'of therestricted port 81 is less than thatof the restricted port 111,V so

that normally, the port 81 governs the time required to effect the blow down of fluid pressure in thel reservoiry 82, but in the case of a.-

short train, the valvepiston 71 will be held y* in its upper position, for Valthough it will initially connected to t-hey upper face, the

`valve piston willbe moved to its upper position when the discharge valve 15 opens. The rate of blow down from the reservoir 82 is then governed by the restricted port 111.

-move downwardly when'the reservoir 821s A While the above described operations taking place, fluid isralso being vented `from the reservoir 67 through the restricted port 70 to tlieiexhaustpoi't23 and after a'predetere ilnined time, say thirty seconds, the pressure.

"1n gthev reservoir 6.7 and in-chamber will j Y .tion with lawhrake pipe,.0i means Vfor effectioV so usto connect the irst reduction reservoir- 'with the second,reductionreservoir 51.

fhejredueed -suiiiciently-,to permit the :piston 61 tohe .shifted outwardly Vby theV spring 62. The-valvef't) Will then he unseated, und fluid `under pressure will -he ventedv vfrom. piston chamber. ,42 by Way of the exhaust port 6.3.

- If piston l1 has not :previously heen'shift-V ed toA itsouter position, it Willnow be shifted,

r vresult is-that if the second reduction in brake 'iv-the movement lof :the

.pipe .pressure shouldahe-held buck for a longer period thanire'quiied to. gather slack, thenrthev pistonil:and .valve .60 will function to-eiiect pistonV ll :to its second l,stagereductionposition; v

Having now described ymy invention, `what Iielaim aslnew `and desire to secure-hy 'Lets 11.1In a fluid :pressure brake, the combination with ahra-ke pipe, of means `for effecting suecessivereductions in brake-pipe pressure including-a coiitroliingvelvedevice, a 1reservoir' normallyicliarged with vfluid under pressure, and .linea-nsfoperative to initiateftlieiirst re-duction finbrafliepipe pressure and to sup.- yply fluid'iirom said `reservoir to said controlfling-valvedevice.

2, *Ina fluid `pressure brake, the combination Witliajbrake vpip.e,=o.f means for effecting Vsuccessive reductions in brake pipe pressure 1 including va .controlling valve fdevice, a resera predetermined rate.

Y `suf-re ,for supplying fluid under pressure to.

voir normally charged Withlflu-id under pressure, means operative to initiate the rst re-k. -ductionin brake pipev pressure and to supply -lufid fromsaid reservoir to .said controlling vulve' device, and' :means for venting Huid from said reservoir and said valve ydevice at ,3. In :a lfluid pressure brake, the :combinatioiifwit'li iii-brake pipe, .of means for effecting Y successive reductions in brake pipe pressureZ including af vtimingvv reservoir,S a .controlling valvedeiiice operated .by Huid underv pi'es- 1 said @timing reservoir., Va reservoir normali-v charged with 'fluid iin-der pressure, and means operative to initiate-the .iirst reductioii'pin hralre pipe `pressure and to supplyjfluidunder pressure from said normally,clizirgedresen Voir tosaidcontrolling valvedeviee. 'Y

fill. In aiiuid pressure hraflre,tlielcoinbinau in with a brake'pipe,'oifineafns foreifecting "successivereductions in brake pip-e `pressure including a controlling .valve device inoyahle to f one-:position by fluid Y un der pressure, la l discharge vvalve device for venti-ng luid under pressure freni the brake v pipe Y i,

ac lfischarge Y .passagehaving la restricted por-t :open tothe atmospherdiiuid under pressure .from said f ,controlling vulve' dev-ice heiiig vented `to said discharge passage through a restricted port,l f". and, coiitiolliiig:az from.; said The controlling .valve device around said Vre-` stricted port `to said discharge passage,v

A5.- In a Huid pressure brake, `the combinaing successive reductions in'bralze v'pipe ,pres sure including a timing reservoir, a controlling l,valve device operatedv hy Vfluid under `pressure for supplying uidl under pressure to saidtiming reservoir, afreservoii' :normally i tion with@y `bralie pipe,"'of means f'oiret'iecting successive reductions in brake pipe'pressure lincluding la viii-st reduction reservoir, a second reduction reservoir, a fluid pressure controlled valve device for controlling: v'conm munication from the irst'to the second reduction reservoir, a valve means operated upon apredetermined reduction in ViluidV pressure Vfor venting fluid from said Avallvedevice, and

means operated fupon i change Vin the signal indication io'r venting-'fluidfrom said {valve means. y v

7.` In a iiuid pressure brake, the combination with a' brake pipe, of ineens 'foreil'ect- Ving successive reductions in brajke pipe'fpressure, means for delayingitliestaitof the second reductionV in brake .pipe pressure 'fora time period after the iirst reduction fhasheen completedand means 4for ensuring the. start ofthe second reduction after the lapse olf a predeterminedtimegperio'd. -1

8. In 'e :flu-id pressure brake, the com'bina- '.tiongivith a brake pipe, of means .for -eiect ing successive reductions in brake pipe pressure, a fnormallyeharged reservoir, meansopei'ated upon apredetermined reduction in fiiuidpressure in said reservoir for ystai-tinge second reduction in brake pipe pressure, a second normallyv charged reservoir, and `additional' means Voperated upon a predetermined reduction in :pressure inthe second reservoir for starting the second reduction in brake pipe pressure.` Y

9.- In a iuid:pressure brake, .theV combination with e bra-1repipe,.of`means for -eiiecting a lreduction, in brake'pipe pressure 'in two stages including rifluid pressure controlled yvalve 'dev-ice movable. to a position in which theisecon'd reduction iii brake pipe pressure started, a timing reservoir, tliepiessure in Wliie'h acts'onsaid valve dev-ice,` a normally charged reservoir, meu-Ins? voperated?"upon Va predetermined redi-ietion lin''press'ure `iii-said 'normally charged' reserveirV for ven ting' fil u i d Y' Virem said timing reservoir und said vulve-device, 1a, second normally.. Vcharged reservoir, and means y operated upon Vlpredeterinined reduction in pressure iin said `second normailv charged reservoir for venting iliid fromsflid timing reserveirenali said ifelse device.;

10. In a fluid pressure brake, the combination with a brake pipe, of means for effecting a reduction in brake pipe pressure in two stages including a lirst4 reduction reservoir, a second reduction reservoir, a valve device operated upon a reduction in fluid pressure for connecting the first reduction reservoir with the second reduction reservoir, a controlling valve means for controlling the fluid pressure on said valve device, a normally charged reservoir, and means for supplying fluid under pressure from said normally charged reservoir to said controlling valve means..

11. In a fluid pressure brake, the combination with a brake pipe, of means for eiecting a reduction in brake pipe pressure in two stages, including a controlling valve device operated by variations in fluid pressure, a reservoir, and an application valve device having one position in which said reservoir is charged with fluid under pressure and another position in which said reservoir is conmy hand.` Y

EARLE S. COOK. 

